Abundant Weed?

Good morning everyone, I was helping myy friend in their garden yesterday and there is loads of the below plant growing in gravel paths around her house. It is very shallow rooted and the bees seem to like it but not sure what it is. I pulled a lot out!

At our last house our neighbour had one plant - three years later it was popping up all over our garden too, despite us pulling up every one we saw. The neighbour's landlord had to mow it down and use membrane and shingle after that tenant moved out!

The seedlings are easily recognised and can be pulled up' just leaving a few to flower, i love them. let the bees enjoy them then compost . as u said roots are so small its easy to pull up.

As I said, I lived next door to an idiot who tried to recreate his hippy youth and planted these things in an inner city back garden and let them grow totally uncontrolled - we moved out some 5 years afterwards and were still pulling the blessed things up every few days throughout the spring and summer - when we visit former neighbours they are still complaining about it. They catapult their seeds over 6 ft high fences and have spread along the gardens of the whole street - they are a total pain - and anyway, I didn't say 'Help!' I said Aaargh! and I meant it.

If it is impatiens balfourii, not the dreaded knotweed, they are smaller and quite pretty. But my daughter gave me some and now they are everywhere, but they are easy to pull up. But I wish I'd never had them in the first place.

Hi. Himalayan (?) Balsam (or Policemans helmet). Had a mass of this growing along the river bank at first address and very handsome it looked - its seeding mattered not there either. I am only posting this because the plant brings to my mind a little something that happened years ago with it - can't be around as long as I have without you gather a few stories. Pal of mine had never ever grown this in he's garden and had lived in that property for years - still does - I am going back to seventies when this occured. He has a walled garden with a border all around at its base. Having cleared the garden that Autumn at Guy Fawkes night decided to just light a smallish fire for the childrens (supervised) fireworks. This burnt the border bare in this area. In spring on that spot came up masses of seedlings of this plant - goodness knows how long those seeds had laid dormant there just waiting for (presumably) this stimulant. Any thoughts?.